* without changing the iterator's state, using the {@link #hasNext} method. But many data sources,
 * such as {@link java.io.Reader#read()}, do not expose this information; the only way to discover
 * whether there is any data left is by trying to retrieve it. These types of data sources are
 * ordinarily difficult to write iterators for. But using this class, one must implement only the

 * without changing the iterator's state, using the {@link #hasNext} method. But many data sources,
 * such as {@link java.io.Reader#read()}, do not expose this information; the only way to discover
 * whether there is any data left is by trying to retrieve it. These types of data sources are
 * ordinarily difficult to write iterators for. But using this class, one must implement only the